The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Various Questions about crust, "layers", acidity, and more!

Quigley's picture

Various Questions about crust, "layers", acidity, and more!

Hey all, I’ve been plugging away with my bread baking, altering recipes and times to try and see what I end up with.  It’s like chemistry lab with no grade!  I have not ended up with a horrible loaf yet, but I’ve seen a few interesting things in my loaves, and heard mention of a couple others, that make me curious about a few different aspects of my baking, so here goes, and thank you so much in advance for any and all help!

1. Crackly bubbles on crust exterior: I started my baking education with the Tartine method, and would end up with big round crackly loaves, however with a couple of more recent loves where I’ve lowered hydration, used 100% or close to 100% KABF, and actually kneaded instead of stretch and folds, I’ve seen a smoother crust without the small (1/2 cm?) russet-colored surface bubbles on the crust itself.  Can you tell me what about these loaves is making the crust stay more uniform and smooth?  Is there a aspect of sugar content or some other ingredient of whole wheat that promotes this surface bubbling?  Could I have created a skin of sorts with unabsorbed flour that would prevent liquid bubbling on the surface?  I’m not sure this is a flavor issue, I just like the look of it.

2.  “Layers” within crumb: Somewhat related to number 1, in one of my loaves I knew I might have a problem when I went for final shaping, and stretched the loaf out into a disk.  This was my first time with a lower hydration, and in retrospect, I don’t think I needed to reshape at all…  The dough had a bit of a skin, not super dry, but visible whiteness from unabsorbed flour where I had turned the loaf out onto the counter, and I folded it into the middle letter-style.  The loaf turned out very well, and had great oven spring and very even crumb, but there are clear “layers” where I folded the dough together.  When pulled apart, the crumb feels the same between any two layers as the inside of a normal hole in the crumb.  Is this due to the skin created from driying out?  Could it be from the oil coating the bowl I proofed in? Is it related to the unabsorbed flour on the somewhat dry side?

These next ones are more unique and/or general:

3. Acidity: I’ve heard recently that too much acidity in a starter can lessen the ability of lactobacillus to thrive, and will impact my ability to get sour bread.  Is this true?  Also, how do you recommend testing for acidity, and what methods can be used to lower the acidity of a starter?

4. Rise, “Doubling”, and Oven Spring:  I get very little rise during fermentation (10-15%?) and just a bit more during proofing (20-25%), but I have excellent oven spring with even bubble distribution, and with the wetter dough I usually use, I get very open crumb.  Am I using a good steam environment as a crutch for rising or is this normal?  Should I be concerned about my starter at all? 

5.  In the Tartine recipe, it calls for creation of about 400g of levain, and then has you only use half for the bread itself.  I keep the starter and feed that instead of using the leftover levain as my replacement starter, so in the interest of waste, what factors will be impacted by using ALL of the levain in the dough build?  I’m not interested in doubling the recipe, but if I use all of the levain, can I expect the dough to develop faster?  Would this mean a shortening of the bulk ferment AND proof, or just the proofing stage?  Does twice as much levain in a build equate to half as much time?

Thanks all!


cranbo's picture

Crackly bubbles are most related to long cold fermentation. They are perhaps also related to higher hydration and long fermentation (cold or not). I also believe they are related to dough strength and shaping. 

Layers do indeed have to do with a skin forming on your loaf during shaping, extra flour or other factors that cause the dough surface to stay dry and not bond with the interior of the dough. It's possible that using a lot of oil could cause this. This is sort of the "cinammon roll" effect: when shaping dough whose outside layer has been modified before re-shaping, you end up with dough separation in a kind of swirl. 

You can lower the acidity of starter by: feeding with less whole grain (more white flour) and keeping a more liquid starter (100% or higher hydration). You can measure acidity using pH strips or a pH meter.  There are lots of TFL threads on this. 

If you're getting very little rise during proofing it means you are not proofing long enough. With sourdough (depending on its level of activity and overall % in relation to the formula) it can take many hours (4-8 at room temp for bulk fermentation is not unusual). The general goal for bulk fermentation is a little less than doubling of volume. It may take some changes to your starter feeding schedule (frequency, amount, temp) and fermentation plan (temp, duration) to get this outcome.  Watch the dough not the clock :) If you're happy with your loaves then who cares ;) 

Yes, more levain = faster for all stages, but it will have effect on texture and flavor of the outcome. I haven't tested it myself, but I don't think 2x the levain will cut times in 1/2. Experimentation is in order, in this case watch the dough and the clock. :)

dabrownman's picture

the Tartine method of starter using room temperature, white flour, high hydration, frequent feedings and lots of waste will not promote acid or sour in bread.  You don't have to worry about acid at all.  Labs like cold and hot and yeast do not.   So to promote lab reproduction and reduce yeast in starters, you need cold and hot (36 F and 86F).  Yeast love wet but Labs are not as adversely affected by low hydration.  Labs love whole grains.  Labs are not as adversely effected by acid as yeast.

So to promote acid, sour and Lab reproduction rates wile limiting yest reproduction you want a stiff (60-66%) starter stored at 36F and fed whole rye and ww or a mix of both  By doing this you will produce 3 times as many labs a yeast which means when you use the starter it will inoculate your bread with way more labs than yeast  making for a way more sour bread. where the labs cane work longer since the dough is slower to proof since the yeast inoculation was reduced.

t room temperature labs and yeast reproduce at the same rate but above 85F labs again reproduce at 3 times the rate of yeast.  So high temperature final proof also promotes sour bread.  Not feeding a stiff, rye starter stored at 36 F also reduces waste to zero if you don;t keep more than 100g after building it and bake a couple of loaves of bread a week

The Tartine method is designed to produce the lest sour bread possible a seeming trademark of SFSD bread today,  It is not a problem as some folks like bread that is less sour,  It depends what you like

Happy baking.

golgi70's picture

interesting post dab.  I ate a piece of Tartine many moons ago (five years0 and just once and it was not fresh from the bakery so it isn't an incredibly fond memory.  It was a good bit I recall but not mindblowing like I've read.  It does though in all its videos and pcitures look amazing.  Now I strangely just made this for the first time yesterday with some minor changes.  I was actually hangin with a colleague and we set out to make lots of pastry and food all day for fun.  We made cocoa macarons with raspberry ganache, a local favorite brownie that we stumbled up the recipe of, some coconut sarahs from Alice Medrich's "Bittersweet" (these are so good) but we used an unwhipped caramel ganache.  I made more pizza dough and I quickly threw together the tartine recipe for a few small loaves.   

Anyway I had my coworker build me the leavain for me to pick up the following day. Accidentally I had him make double and just opted to go forward with it.  It took about 3 1/2 hours to bulk ferment with 5 sets of slap/stretch and folds.  It was very wet dough.  Shaping was fun.  Instead of the overnight retard after an hour in a hot kitchen I threw them in the fridge for about 3 hours while I heated my stones.  I baked them directly from the fridge.  Fresh these were great and did have a nice touch of sour.  Not overwhelmingly so but deffinately sour.  I bet these would have been just amazing had I 1)made them larger loaves and 2) let them retard for the entire 8 - 12 hours.  

Maybe the starter I keep that is fed daily and then retarded a few hours later is my secret to sourness. 

I'm gonna have to go back and try the real deal soon.  


dabrownman's picture

say 20 g and retard that for 2 days.  Then build a levain out of it over (2) 4 hour builds and 1 one hour build to say 200 g for a large loaf and then refrigerate that for 24 hours.  Then let the levain finally double on the counter before using it to make your Tartine bread.  Retard the dough for say 24-30 hours and then get it to room temp and bake it off.  Then you can compare that sour with your normal one and see which one you like best and which one is more sour.  I was quite taken back with the difference.  Like night and day - especially when the bread is a day old.  It is fun to experiment with bread stuff!

Happy baking